JavaScript拖拽的对话框

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
    <style>
        .login-header {
            width: 100%;
            text-align: center;
            height: 30px;
            font-size: 24px;
            line-height: 30px;
        }

        ul, li, ol, dl, dt, dd, div, p, span, h1, h2, h3, h4, h5, h6, a {
            padding: 0px;
            margin: 0px;
        }

        .login {
            width: 512px;
            position: absolute;
            border: #ebebeb solid 1px;
            height: 280px;
            left: 50%;
            right: 50%;
            background: #ffffff;
            box-shadow: 0px 0px 20px #ddd;
            z-index: 9999;
            margin-left: -250px;
            margin-top: 140px;
            display: none;
        }

        .login-title {
            width: 100%;
            margin: 10px 0px 0px 0px;
            text-align: center;
            line-height: 40px;
            height: 40px;
            font-size: 18px;
            position: relative;
            cursor: move;
            -moz-user-select: none; /*火狐*/
            -webkit-user-select: none; /*webkit浏览器*/
            -ms-user-select: none; /*IE10*/
            -khtml-user-select: none; /*早期浏览器*/
            user-select: none;
        }

        .login-input-content {
            margin-top: 20px;
        }

        .login-button {
            width: 50%;
            margin: 30px auto 0px auto;
            line-height: 40px;
            font-size: 14px;
            border: #ebebeb 1px solid;
            text-align: center;
        }

        .login-bg {
            width: 100%;
            height: 100%;
            position: fixed;
            top: 0px;
            left: 0px;
            background: #000000;
            filter: alpha(opacity=30);
            -moz-opacity: 0.3;
            -khtml-opacity: 0.3;
            opacity: 0.3;
            display: none;
        }

        a {
            text-decoration: none;
            color: #000000;
        }

        .login-button a {
            display: block;
        }

        .login-input input.list-input {
            float: left;
            line-height: 35px;
            height: 35px;
            width: 350px;
            border: #ebebeb 1px solid;
            text-indent: 5px;
        }

        .login-input {
            overflow: hidden;
            margin: 0px 0px 20px 0px;
        }

        .login-input label {
            float: left;
            width: 90px;
            padding-right: 10px;
            text-align: right;
            line-height: 35px;
            height: 35px;
            font-size: 14px;
        }

        .login-title span {
            position: absolute;
            font-size: 12px;
            right: -20px;
            top: -30px;
            background: #ffffff;
            border: #ebebeb solid 1px;
            width: 40px;
            height: 40px;
            border-radius: 20px;
        }


    </style>
</head>
<body>
<div class="login-header"><a id="link" href="javascript:void(0);">点击,弹出登录框</a></div>
<div id="login" class="login">
    <div id="title" class="login-title">登录会员
        <span><a id="closeBtn" href="javascript:void(0);" class="close-login">关闭</a></span></div>
    <div class="login-input-content">
        <div class="login-input">
            <label>用户名:</label>
            <input type="text" placeholder="请输入用户名" name="info[username]" id="username" class="list-input">
        </div>
        <div class="login-input">
            <label>登录密码:</label>
            <input type="password" placeholder="请输入登录密码" name="info[password]" id="password" class="list-input">
        </div>
    </div>
    <div id="loginBtn" class="login-button"><a href="javascript:void(0);" id="login-button-submit">登录会员</a></div>
</div>
<!--登录框-->
<div id="bg" class="login-bg"></div>
<!--遮挡层-->
<script src="common.js"></script>
<script>
    //点击显示遮挡层和登录框
    my$("link").onclick = function () {
        my$("login").style.display = "block";
        my$("bg").style.display = "block";
    };
    //点击隐藏遮挡层和登录框
    my$("closeBtn").onclick = function () {
        my$("login").style.display = "none";
        my$("bg").style.display = "none";
    };
    //按下鼠标,移动鼠标,移动登录框
    my$("title").onmousedown = function (e) {
        //获取此时可视区域的横坐标-此时登录框距离左侧页面的横坐标
        var spaceX = e.clientX - my$("login").offsetLeft;
        var spaceY = e.clientY - my$("login").offsetTop;
        //移动事件
        document.onmousemove = function (e) {
            //登录框新的可视区域的横坐标 = 鼠标当前可视区域的横坐标 - spaceX
            var x = e.clientX - spaceX;
            //登录框新的可视区域的纵坐标 = 鼠标当前可是区域的纵坐标 - spaceY
            var y = e.clientY - spaceY;
            my$("login").style.left = x + 250 + "px";
            my$("login").style.top = y - 140 + "px";
        };
        //抬起鼠标
        document.onmouseup = function () {
            document.onmousemove = null;
        };
    };

</script>
</body>
</html>

common.js

/**
 * Created by Administrator on 2018/8/18.
 */
/**
 * Created by Administrator on 2016/7/27.
 */
/**
 * Created by Administrator on 2016/7/21.
 *
 * 次文件来自  很牛x的程序员 .
 *
 * 作者:无名
 */

/*
 * 该函数是返回的是指定格式的日期,是字符串类型
 * 参数:date ----日期
 * 返回值: 字符串类型的日期
 * */
function getDatetoString(date) {
    var strDate;//存储日期的字符串
    //获取年
    var year = date.getFullYear();
    //获取月
    var month = date.getMonth() + 1;
    //获取日
    var day = date.getDate();
    //获取小时
    var hour = date.getHours();
    //获取分钟
    var minute = date.getMinutes();
    //获取秒
    var second = date.getSeconds();
    hour = hour < 10 ? "0" + hour : hour;
    minute = minute < 10 ? "0" + minute : minute;
    second = second < 10 ? "0" + second : second;
    //拼接
    strDate = year + "-" + month + "-" + day + " " + hour + ":" + minute + ":" + second;//隐藏问题,关于变量声明的位置
    return strDate;
}

//根据id获取元素对象
function my$(id) {
    return document.getElementById(id);
}


/*
 *
 * innerText属性IE中支持
 * textContent火狐中支持
 * dvObj.innerText="您好";设置innerText的值
 * console.log(dvObj.innerText);获取innerText的值
 * 因为上述原因,inerText有时候需要设置值,有时候需要获取值
 * 所以,需要写一个兼容的代码能在火狐中使用,也可以在IE中使用
 *
 *
 * */

/*
 *设置innerText属性的值
 * element-----为某个元素设置属性值
 * content-----设置的值
 * */
function setInnerText(element, content) {
    if (typeof element.textContent === "undefined") {
        //IE浏览器
        element.innerText = content;
    } else {
        element.textContent = content;
    }
}
/*
 * 获取innerText属性的值
 * element 要获取的元素
 * 返回的是该元素的innerText值
 * */
function getInnerText(element) {
    if (typeof element.textContent === "undefined") {
        //IE浏览器
        return element.innerText;
    } else {
        return element.textContent;
    }
}


//获取当前元素前一个元素
function getPreviousElement(element) {
    if (element.previousElementSibling) {
        return element.previousElementSibling;
    } else {
        var ele = element.previousSibling;
        while (ele && ele.nodeType !== 1) {
            ele = ele.previousSibling;
        }
        return ele;
    }
}
//获取当前元素的后一个元素
function getNextElement(element) {
    if (element.nextElementSibling) {
        return element.nextElementSibling;
    } else {
        var ele = element.nextSibling;
        while (ele && ele.nodeType !== 1) {
            ele = ele.nextSibling;
        }
        return ele;
    }
}

//获取父元素中的第一个元素
function getFirstElementByParent(parent) {
    if (parent.firstElementChild) {
        return parent.firstElementChild;
    } else {
        var ele = parent.firstChild;
        while (ele && ele.nodeType !== 1) {
            ele = ele.nextSibling;
        }
        return ele;
    }
}
//获取父元素中的最后一个元素
function getLastElementByParent(parent) {
    if (parent.lastElementChild) {
        return parent.lastElementChild;
    } else {
        var ele = parent.lastChild;
        while (ele && ele.nodeType !== 1) {
            ele = ele.previousSibling;
        }
        return ele;
    }
}

//获取兄弟元素
function getsiblings(ele) {
    if (!ele)return;//判断当前的ele这个元素是否存在
    var elements = [];//定义数组的目的就是存储当前这个元素的所有的兄弟元素
    var el = ele.previousSibling;//当前元素的前一个节点
    while (el) {
        if (el.nodeType === 1) {//元素
            elements.push(el);//加到数组中
        }
        el = el.previousSibling;
    }
    el = ele.nextSibling;
    while (el) {
        if (el.nodeType === 1) {
            elements.push(el);
        }
        el = el.nextSibling;
    }
    return elements;
}
//    //能力检测多个浏览器为同一个对象注册多个事件
var EventTools = {
    //为对象添加注册事件
    addEventListener: function (element, eventName, listener) {
        if (element.addEventListener) {
            element.addEventListener(eventName, listener, false);
        } else if (element.attachEvent) {
            element.attachEvent("on" + eventName, listener)
        } else {
            element["on" + eventName] = listener;
        }
    },
    //为对象移除事件
    removeEventListener: function (element, eventName, listener) {
        if (element.removeEventListener) {
            element.removeEventListener(eventName, listener, false);
        } else if (element.detachEvent) {
            element.detachEvent("on" + eventName, listener);
        } else {
            element["on" + eventName] = null;
        }
    },
    //获取参数e
    getEvent: function (e) {
        return e || window.event;
    },
    getPageX: function (e) {
        if (e.pageX) {
            return e.pageX;
        } else {
            //有的浏览器把高度设计在了文档的第一个元素中了
            //有的浏览器把高度设计在了body中了
            //document.documentElement.scrollTop;//文档的第一个元素
            //document.body.scrollTop;
            var scrollLeft = document.documentElement.scrollLeft || document.body.scrollLeft;
            return e.clientX + scrollLeft;
        }
    },
    getPageY: function (e) {
        if (e.pageY) {
            return e.pageY;
        } else {
            var scrollTop = document.documentElement.scrollTop || document.body.scrollTop;
            return e.clientY + scrollTop;
        }
    }

};
原文地址:https://www.cnblogs.com/cuilichao/p/9513988.html